Method for rendering fibrous material oil and water repellent



United States Patent 3,476,583 I METHOD FOR RENDERING FIBROUS MATERIALOIL AND WATER REPELLENT Vincent Theodore Elkind, Metuchen, Joseph AloyusYurko, Bayonne, and Robert Tweedy Hunter, Piscataway, N.J., assignors toColgate-Palmolive Company, New York, N.Y., a corporation of Delaware NoDrawing. Filed Oct. 30, 1967, Ser. No. 679,196 Int. Cl. B44d 1/44 US.Cl. 117-63 Claims ABSTRACT OF THE DISCLOSURE a This invention relates toa method and means for achieving a degree of oil and/or water repellencyin fibrous materials by treating such materials as textiles and the likewith a fluorocarbon polymer and achieving the desired oil and/or waterrepellency by activation with a curing solvent, such as unsymmetricaltrichlorotrifluoroethane, and wherein the solvent'has incorporatedtherein an adjuvant for the solvent to thereby increase the curingactivity thereof.

It is known that textile materials can be made water resistant and oilrepellent by treating them with aqueous solutions or.dispersions of.organic compounds which contain a plurality of perfluoroalkyl radicals.After such treatment, in the past, it has been necessary to activate theoil and water resistant properties by curing techniques such as oven orhot iron treatment. It will be appreciated that oven techniques cannotreadily be utilized in conjunction with textile materials in the home.While ironing techniques, on the other hand, may be easily utilized inthe home, the ironing of pile type material or already applied fibrouswall paper is virtually impossible. A technique avoiding the prior artcure methods Would be appreciated as giving wider usage to the use offluorocarbon polymer compounds in establishing a degree of water and oilrepellency for various materials. While some progress has already beenaccomplished in this direction by employing fluorocarbon polymers whichhave been activated with a solvent therefor, the effectiveness has notbeen deemed as good as desired.

Accordingly, the present invention relates to a method for developingoil and water repellency in fibrous inaterials, such astextilematerials, comprising treating such materials with a fluorocarbonpolymer in water, for instance;. then drying said treated materials;thereafter treating the materials to an activation and curingcomposition to achieve the water and oil repellency benefits of thefluorocarbon polymer. The composition comprises a solvent for thefluorocarbon polymer and a material which retards the evaporation of thesolvent whereby better curing is effected.

The fluorochemical compounds, which are used to impart water and oilrepellent properties, can have chemical structures that vary. Widely.For example, acrylates and methacrylate of hydroxyl compounds containinga highly fluorinated residue and their polymers and copolymers can beused. Fluorochemical compounds of this type are defined with greaterparticularity in US. Patent Nos. 2,642,416, 2,826,565, 2,829,513 and2,803,615. Other fluorochemical compounds which can be employed as oiland water repellent agents include the chromium coordination complexesof saturated perfluoromonocarboxylic acids of which the chromiumcomplexes perfluorobutyric acid and perfluorooctanoic acid arerepresentative. Fluorochemical compounds suitable for the process of theinvention are available commercially, many of which have been patentedand assigned 3,476,583 Patented Nov. 4, 1969 to the Minnesota Mining andManufacturing Company, for example those having the following formula:

where X is an integer in the range of 3-13, R is methyl, ethyl, propyl,butyl, amyl, hexyl, R is an alkylene radical having l-12 carbon atomsand R is hydrogen, methyl or ethyl. Other applicable fluorochemicalcompounds are compounds manufactured by DuPont, such as polymers of1,1,7-trihydroperfluoroheptyl acrylate; l, 1,7-t-rihydroperfluoroheptylmethacrylate; 1,1-dihydroperfluorooctyl methacrylate and a te-rpolymerlatex product consisting of 97.6% perfluoromethacrylate monomer, 2%butyl acrylate and 0.5% N-methylol acrylamide.

The applicable activation solvent may be one or more of the followingsolvents: unsymmetrical trichlorotrifluoroethane, 1,3 hexafluoroxylene,trifluorotoluene and tetrahydrofuran with an additive such as anaromatic alcohol ether, aromatic ester and/or aliphatic ester, such asterpeneol, phenylethanol, amyl salicylate, benzyl acetate and essentialoils. While it is not specifically known as to how the additivefunctions to enhance activation of the curing solvent, it is believedthat solvent evaporation is retarded so that curing may be effected fora longer period of time after application to the substrate.

The techniques attendant the present invention may be utilized inconjunction with fibrous, porous and contin uous surfaces. Illustrativearticles to be treated are textiles, glass, paper, wood, leather, fur,asbestos, bricks, concrete, metals, ceramics, plastics, painted surfacesand plaster. Due to the advantages incident to the repellency to oil andwater and their resistance to soiling imparted by carrying out thetechniques of the present invention; the preferred classes of articlesto be treated are textile apparel, upholstery, draperies, carpeting,paper bags, cardboard containers, luggage, handbags, shoes, jackets,redwood, pine cedar and asbestos siding materials, bricks, concrete,floor or wall tiles, painted or unpainted metals such as appliances andautomobile bodies, masonry, wood plaster, wallpaper and wallboardsurfaces. In the treatment of fabrics 0.05 to 5% (preferably 0.1 to 1%)by weight of the fluorocarbon polymer on the weight of the fabricproduces desirable surface properties. Illustrative textiles which canbe advantageously treated with the fluorocarbon polymer are those basedon natural fibers, e.g., cotton, wool, mohair, linen, jute, silk,rarnie, sisal, kenaf, etc., and those based on synthetic fibers, e.g.,rayon, acetate, acrylic, polyester, saran, azylon, nytril, nylon,spandex, vinyl, ole'fin, vinyon and glass fibers. (These designations ofsynthetic fibers are the generic terms set up by the Federal TradeCommission.) The treatment of these fabrics with the compositions ofthis invention imparts no adverse effect to the hand of the fabric andin some cases has a softening effect, thereby improving the hand.

The fluorocarbon polymer may be applied as a surface treatment by knownmethods of coating such as spraying, brushing, or impregnation from anaqueous or organic solvent dispersion or an organic solution of thefluorocarbon polymer. The fluorocarbon polymer may be used as the solecomponent in the treating vehicle or as a component in a complexmulti-ingredient formulation.

The amount of the fluorocarbon polymer used in the impregnating solutionmay be varied within wide limits, depending on the type of substrateemployed and on the end use requirements for water repellency, oilrepellency and durability. The following ranges are preferred, and

giveexcellent results on many types of substrates, such as fabrics:

(a) 1% to 5% of an aqueous dispersion of the fluorocarbon polymercompound (about 30% active ingredient).

(b) Surfactant may vary from 6% The activation composition is applied byemploying one of numerous methods. For instance the solvent-additivecomposition may be applied by brushing or spraying the previouslyfluorocarbon polymer treated polymer substrate with the composition.While the substrate, if possible, may be immersed in a bath containingthe composition, it will be appreciated that the adjuvant is primarilyeffective as a solvent retardant when the substrate has been removedfrom the bath. Therefore, the use of the adjuvant finds its greatestapplicability under those conditions where the curing solvent is appliedas a coating to the substrate as by brushing or spraying.

In the activating composition, the following quantities are applicable:

(a) Small but effective 'amountto wetness of the substrate of theselective curing solvent;

(b) A small but perceptible amount of the additive-- to about of theweight of the selective curing solvent.

The following specific examples will further illustrate the practice ofthe invention, but are not to be deemed to limit the scope of theinvention to any procedural or other details there set forth.

EXAMPLE I Cotton swatches having 80x80 count were treated in an aqueousmedium containing polyperfluoroalkyl methacrylate and surfactant,namely, N-hyd'rogenated tallow N, N diisopropanol N-methyl methylsulfate. The quantity of the polyperfiuoroalkyl methacrylate in theaqueous medium was such so as to deposit 0.25% by weight of the weightof fabric and similarly, the surfactant was in a quantity of 0.33% byweight of the fabric. The medium was acidified with acetic acid to a pHof 5.

After exhausting the fluorocarbon polymer on the swatches, the swatcheswere removed from the treating medium and air dried at room temperature.The thereby treated specimens had a fair water repellency.

One group of swatches was then brushed with Freon 113 (unsymmetricaltrichlorotrifluoroethane). The swatches so treated developed a betterrepellency than those not given a solvent curing treatment. Theremaining group of swatches was then brushed with Freon 113(unsymmetrical trichlorotrifiuoroethane) containing 1% terpeneol. Theseswatches were then dried at room temperature. Theseswatches developedthe best repellency.

EXAMPLE II This example illustrates the further concept of treatingfabrics in a mill with the fluorocarbon polymer fol lowed by idrying andactivation by application of the selective curing agent composition ofthe present invention. Illustratively, rolls of cotton were run througha padder where the cotton was treated to an 80% wet pick-up of aformulation comprising 3.5% by weight of a polymer of1,1,7-trihydroperfluoroheptyl acrylate, and 0.35% nonylphenoxypolyoxyethylene ethanol nonionic surfactant, the remainder beingwater. Then the roll of wet cotton was passed through an oven at 250 P.where it was dried for five minutes. The cotton was then cooled to .roomtemperature. Thereafter, the cotton was conveyed to a chamber wherein itwas sprayed with 1,3- hexafluoroxylene containing 2% terpeneol. From thechamber,;the roll of cotton is passed intoa sealed compartment, wherethe Vapor of the selective solvent was efiicientlyrecovered. The cottonso treated exhibited a high degree ofwater and oil repellency.

Several tests can be employed to establish the effectiveness of thepresent process for imparting water repellent and oilrepellent'properties to the various substrates.

While a number of tests have been devised to determine the degree ofstain resistance of fabrics and the subsequent launderability thereof,many of the tests fail by reason of the difficulty of making such testsconsistently reproducible. Colgate-Palmolive research scientists havedeveloped an ingeniouslest systemwhich oyerc omes the shortcomings ofthe previous tests. Essentially, their method consists of placing ontothe fabric measured volumes of standard common staining materials andcomparing the size and intensity to a visual standard. In this way asemi-quantitative estimation of the staining characteristics of a givenfabric is obtained.

The test technique employs three water borne stains, namely, (1)chocolate milk, (2) black coffee and (3) imitation Coke and three oilborne, stains, namely, (4) blue dyed corn oil, (5) French dressing and(6) blue dyed petroleum oil. t

The staining materials mentioned in the above have the followingcompositions:

This stainshould be prepared. once a weekandfkep t refrigerated. I V v(2) Black coffee Instant coffee 1.5 Boiling water 98.5

The coffee solution is allowed to cool until it'reaches 70-80 F. Thestain should not be kept for more than eight hours. The coffee stainshould be freshly prepared on a daily basis.

(3) Imitation Cokej ring and heat in order to obtain a uniform solution.

(5) French dressing Once a bottle is opened, it should be stored in arefrigerator.

(6) Blue. dyed petroleum-oil 2'50'grams of oil-aremixedwith 0.1% bluedye by weight'of the oil. The'mixture is agitated and warmed in order'to obtain a uniform solution;

The 'test in the instant case is a static stain repellency test in thatthe fabric surface isgiven a minimum disturbance. Y I

In application the temperature of the stain materials is between 7080 F.A piece of white fabric approximately 7 inches by 7 inches is placed onblotting paper on a hard surface. 1 /2 cc. of each test stain is.carefully placed (not dropped) in separate" areas on the-fabric. Aftentwo minutes, the excess stain material," 'if ai1y,'is removed using avacuum suction line without comingin physical. contact with ,t hestainedsurface. The stained area is'brushed'twicelightly in oppositedirections with a straight motion of a dry absorbent tissue to removeany'unabsorbed stain materials 1 The stains are rated against then-whitebackground of a clean blotter. Ratings of 1 through 5 are arrived atstrictlyron'size (relative spread) of an individual stain while rating 6through 10 determineslrelative' wetting as measuredby intensity of thestainJagainst a standard.

In other words, a stain notaeven wetting thefabric could not change thecolor of the fabricand would have been completely removed from thesurface thereof. The rating, therefore would be 10. With increasingwetting ot the area to which the stain has been applied there would be agreater color intensity therefore a lower rating until 6 is reached,whereupon, if the stain has migrated from What is claimed is:

1. A method for developing oil and. water repellency in connection witha substrate which has been treated with a fluorocarbon polymer selectedfrom the group consisting of polymeric acrylates and methacrylates ofits original boundary then one can assume complete wet- 5 hydroxylcompounds containing a highly fluorinated resting of the original areaso that degree of migration beidue and chromium coordination complexesof satucomes the determining factor. The greater the migration, ratedperfluoro monocarboxylic acids applied to said the lower the numbergiven. It will be appreciated that substrate, wherein the improvementcomprises further the test system is based on relative values, and yetprotreating the treated substrate with a composition con- V s u ique rpr u ible id su t taining a liquid which is a solvent for saidfluorocarbon The three water borne stains are added together to givepolymer, said liquid being selected from the group a Possible maxhhhm ofQ- ih? 011 home Stains sisting of unsymmetricaltrichlorotrifluoroethane, 1,3- are added to glve maxlmum Posslblhty ofThese hexafluoroxylene, trifluorotoluene and] tetrahydrofuran may then,be totalled for a t fi and an adjuvant selected from a group consistingof 1 arnve the laupderabfllty portion of the aromatic alcohols,aliphatic esters, aromatic esters and stauied fabncs are i 24 hoursLtundenng .then essential oils having the property of retardingevaporation carried out by washing 1n an automatic washer with a of theSolvent quantity of a conventional detergent. The fabrics are then 2 Ath f 1 h 1 dried in an automatic dryer at the appropriate setting for meo o c am 1 w erem Sal lqul so vent the fabric type. They are thenlightly dry ironed (stain is lfihexofluowxylene' side down) at theappropriate fabric setting. 3. The method of claim 2 wherein the polymeris a The rating of launderability of stains is based on thePOlyfluomalkylacrylatesame 1-10 system used for the static stainrepellency The method of Claim 1 wherein the adjuvant is tests. Again,it will be noted that the maximum rating Selected from the g pConsisting of p l, p nylafter adding the results of the water bornestains will be ethanol, amyl salicylate and 'benzyl acetate.

30, and similarly will be the total results regarding 5. The method ofclaim 1 wherein the substrate is a the oil borne stains. These two maybe added together. fib t i l,

By rating both the initial static stain repellency and The method fclaim 1 wherein the quantity f the launderability, a complete picturecan be obtained not 30 the Solvent 1 d i up to about equal to thepossible when only the intlal straln reaction 1s determined. Smite by ih hil th dditive employed is about In the follow1ng examples cottonswatches were preup to 5% by weight of the Solvent pared as Example Ianli.spraye.d wlth q' 7. The method of claim 4 wherein the adjuvant isxylene as the solvent plasticlzer with or without an addit 1 tive asindicated in the results set forth in the table on erpeneo this page.The tests were conducted in accordance with The method of Glam 4 Wheremthe adluvant the Colgate-Palmolive test produce mentioned in thePhenylethanol' above. The adjuvant when employed was in the amountmethod of 01mm 4 Wherem the adluvaht 15 of 0.5% based on the Weight ofthe solvent while the y sahcylateweight of the total curing compositionwas about equal 10- The me o 61mm 4 Wherelfl the adjuvant is to thefabric. benzyl acetate.

Colgate-Palmolive Test Repellency Lannderabillty W.B. 0.13. Total W13.03. Total Maximum Rating Example filt'ii gvl fi pi l'fitgfi fi iiiiiilil rith 30 3o 30 30 60 5 e 11 13 6 19 23 13 36 27 s 35 27 20 47 29 24 5329 29 5s 30 29.5 59.5 30 29.5 59.5 30 an 60 30 30 60 30 3o 60 21 25. 552. 5 30 26. 5 56. 5

W.B.=Water borne; 0.B.=0il borne.

References Cited UNITED STATES PATENTS 2,277,941 3/1942 Almy 36772,642,416 6/1953 Ahlbrechtet a1. 260-83.5 2,803,615 8/1957 Ahlbrecht eta1. 260-29.6

WILLIAM D. MARTIN, Primary Examiner THEODOR E G. DAVIS, AssistantExaminer US. Cl. X.R.

